NBER Working Paper No. 16278Issued in August 2010NBER Program(s): CHHELS

Economists have puzzled over why eligible individuals fail to enroll in social safety net programs. "Chilling effects" arising from an icy policy climate are a popular explanation for low program take-up rates among immigrants, but such effects are inherently hard to measure. This paper investigates a concrete determinant of chilling, Federal immigration enforcement, and finds robust evidence that heightened enforcement reduces Medicaid participation among children of non-citizens. This is the case even when children are themselves citizens and face no eligibility barriers to Medicaid enrollment. Immigrants from countries with more undocumented U.S. residents, those living in cities with a high fraction of other immigrants, and those with healthy children are most sensitive to enforcement efforts. Up to seventy-five percent of the relative decline in non-citizen Medicaid participation around the time of welfare reform, which has been attributed to the chilling effects of the reform itself, is explained by a contemporaneous spike in immigration enforcement activity. The results imply that safety net participation is influenced not only by program design, but also by a broader set of seemingly unrelated policy choices.